One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,5,6)(3,7,8,4)(9,10,13,15)(11,14,16,12)(17,18)(19,24)(20,22)(21,23)(26,30)(28,36)(31,33)(34,40)(2,6)(3,8)(9,11,13,16)(10,12,15,14)(17,19,21,22)(18,20,23,24)(26,30)(28,36)(31,33)(34,40)(3,8)(4,7)(11,16)(12,14)(17,20,21,24)(18,22,23,19)(25,26)(27,33)(28,32)(29,30)(31,35)(34,39)(36,37)(38,40)(1,3,5,8)(2,7,6,4)(9,11)(10,14)(12,15)(13,16)(17,20)(18,19)(21,24)(22,23)(25,27,29,35)(26,31,30,33)(28,34,36,40)(32,38,37,39)(1,4,5,7)(2,8,6,3)(9,12,13,14)(10,11,15,16)(17,18)(19,20)(21,23)(22,24)(25,28,29,36)(26,32,30,37)(27,34,35,40)(31,38,33,39)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.